Sharpener for slicing machines



Oct. 25, 1932. w. A. VAN BERKEL SHARPENER FOR SLICING MACHINES i i al Fis p 7. 192: 2 Sheets-Sheet 1 I fizz/62230; WJMAMMW MMX aagzzalfiJill/III Oct. 25, 1932. w. A. VAN BERKEL SHARPENER FOR SLICING MACHINESginal Filed Se t '1, 923

2 Sheets-Sheet 2 Ori Patented Get. 25, 1932,

UNITED STATES} PATENT oFFicE WILHELM'US ADRIANUS VAN IBERKEL, OFCLARENS, MONTREUX, SWITZERLAND,

ASSIGNOR TO U. S. SLICING MACHINE COMPANY, OF LA FORTE, INDIANA, ACORPO- RATION OF INDIANA SHARPENER FOR SLIGING lliIACHINIES' Applicationfiled September 7, 1923, Serial No. 661,383. Renewed September 21, 1931.

This invention relates to sharpeners for rotary disc knives of slicingmachines and has for its object the provision of a sharpening devicewhich shall be economical to manufacture, convenient and efficient inoperation, and of improved construction.

The invention is exemplified in the combination and arrangement of partsshown in the accompanying drawings and described in the followingspe'cificationj and it is more particularly pointed out in the appendedclaims. V 7

In the drawings- V Fig. 1 is a vertical sectional view of one embodimentof the present invention;

Fig. 2 is an elevation of the device-shown in Fig. 1, with parts insection; 9

V Fig. 3 is a top plan view of the sharpener.

with the casing in section, and

Fig. 4 is a cross-section taken substantially along the line 4-4 of Fig.3.

The numeral designates the pedestal for the knife of a slicing machineof any approved construction having a rotary disc knife 11 mountedthereon. The pedestal .10 carries a sharpener support 12 secured tothepedestal by screws 13. This support 12 is provided with a'socket forreceivinga stem 14 7 on which the grinder is mounted. The supportingframe for the grinder includes a cross-bar 15 which carriesa pair ofjournal bearings 16 and 17. The bearing 17 may be formed integrally withan upright plate 18 of the supporting frame, and'the bearing 16 ispreferably provided with an ear or web 19 pivotally mounted on the frameby means of a screw 20. A downwardly projecting ear 21 attached to thebearing 16 is provided with a slot 22 and a cap screw 23 by means ofwhich the hearing 16 may be secured in adjusted angular positions.

Within the bearing 16, as shown clearly in Fig. 1,' is slidably mountedasleeve 24 hav ing a spindle 25 journaled therein. The sleeve 24 isprovided with a shoulder 26 which is disposed opposite a shoulder 27formed on i the inner face of the bearing 16. A coil spring 28 isinterposed between the shoulders 26 and 27 and normally forces thesleeve 24 to the left, as viewed in Fig.- 1. The spindle 24 to take thethrust of the sleeve 24 under the pressure of the spring 28. The spring28 when expanded forces the outer face of the grinder disc 30 againstthe edge of the knife 11, the point of'contact being above the axis ofthe disc.

Y When the knife 11 is rotated the frictional engagement with thegrinder will cause the grinder disc to rotate which will move the faceof the disc across the edge of-the knife for sharpening. The grinderdisc is dished, as shown to provide a. flange 33 for contact with theedge of the knife. Thisprevents any interference between the knife andthe nut 34 which holds the grinder in place on they spindle 25. It alsolocalizes the bearing surface between the knife and disc so that thegrinding takes place only at the portion of the disc having the greatestangularity of movement relative to the periphery of the knife. v

A pin 35 is attached to the sliding sleeve 24 and extends upwardlythrough a slot 36 in the bearing 16. A cam finger 37 engages the pin 35and is attached to a rock shaft 38 journaled in the upper portion of theframe.

The rock shaft 38 is provided with a handle 39 projecting upwardlythrough a slot 40 in the casing or guard member 41.- When the handle 39is in full line position shown in Fig. 1 the sleeve 24 will be held in aretracted position with the spring 28 compressed so that the grinder 30is withdrawn from contact with the knife 11. NVhen it is desired togrind the knife the handle 39 is moved into the broken line positionshown in Fig. 1 which will release the pin 35 and permit the grinder 30to be pressed against the knife 11 by the expansion of the spring 28.

As shown in Fig. 3, a coil spring 42 sure rounds the shaft 38 andnormally rotates the shaft into the full line position shown in Fig.

1 so that as soon as the handle 39 is released the grinder 30 isautomatically retracted from engagement with the knife 11. The grinder30 engages the beveled face of the knife and does the major portion ofthe sharpening. It is desirable, however, to remove any burr from theface of the knife that may be formed by grinding, and a second grinderwheel 43 is provided for this purpose. The wheel 43 is secured to aspindle 44 journaled in a sleeve 45 slidably mounted in the bearing 17.A spring 46 normally forces the spindle 44 inwardly to draw the flatface of the disc 43 against the knife 11. A cam finger 47 engages a pin48 secured to the sleeve '45 and is fixed to the shaft 38 in position tohold the disc 43 away from the knife'll when the handle 39 is in thefull line position shown in Fig. 1. It will thus be seen that when thehandle 39 is operated to bring the disc 30 into contact with the knife11 the same movement will permit the spring 46 to move the disc 43against the flat face of the knife 11. If desired, the parts may beproportioned so that the disc 30 will engage the bevel face of the knifeprior to contact between the disc 43 and the flat face of the knife sothat the stones will act successively, depending on the amount ofmovement of the handle 39. This is not an essential arrangement,however, as the stones may be made to act together. The amount ofgrinding of the two stones may be regulated by the strength of thesprings which control the pressure of the stones against the knife.

It will be noted that the casing 41 is open at the bottom so that it maybe readily placed over the stones and their operating mechanism. It issecured in place by screws 49 and is readily removable for giving accessto the sharpener parts. The flange 50 on the casing forms a guard forthe stones during a grinding operation. A rod or pin 51 projectsdownwardly from the bar 15 in position to engage either one of twoopenings 52 and 53 in a flange 54 on the support 12. In one position thepin 51 holds the grinding stones in operating position relative to theknife 11. When the pin 51 engages the opening 53 the stones are turnedentirely away from the grinding knife. Before the parts can be shiftedfrom one position to the other it is necessary to raise the stones untilthe pin 51 is free from the opening 52. This will bring the stones abovethe edge of the knife so that there is no danger of marring the edgewhen the sharpener is rotated from one position to another.

A spring bar 55 is provided with a. hook 56 underlying the flange 54 toprevent the supporting pin 14 from being entirely removed from itssocket during the changing of the disc from one position to another. Athumb nut 56 is threaded on the pin 51 and regulates theheight of thestones relative to the edge of the knife. Depressions 57 may be providedin the periphery of the nut 56 to enin each sleeve, a grinder discsecured to each spindle andarranged to engage opposite faces of saidknife, springs for resiliently moving said sleeves to press said discsagainst said knife, an abutment member connected with each sleeve, a camshaft extending transversely of said spindles, and positioned betweensaid abutment members, cams on said shaft for engaging said abutmentmembers to retract said grinders against the force of their springs, aspring for operating said cam shaft to retract said grinders, and ahandle disposed at one side of the plane of the knife and movable awayfrom said plane to turn said cam shaft against the force of thelastnamed spring to cause said grinders to engage said knife under theinfluence of the first-named springs, said second-named spring acting tocause the automatic disengagement of said grinders from said knife whensaid handle is released.

2. A grinder for slicing machine knives comprising a supporting frame, aspindle journaled to rotate about a fixed axis in said frame and havinga grinder thereon arranged to engage one face of a knife to besharpened, a second spindle having a grinder thereon for engaging theopposite face of the knife, a support for said second spindle pivotallymounted on said frame and adjustable thereon to vary the angularposition of said spindle relative to the plane of said knife while saidfirst-mentioned spindle retains its position relative to said knife,resilient means for moving said grinders against the respective faces ofsaid knife, cams for retracting said grinders, a cam shaftextending'transversely of said spindles for supporting said cams and asingle handle for operating said cam shaft.

3. A sharpener for slicing machine knives comprising a frame having apair of grinders mounted thereon, a bar on which said frame is'mounted,a socket member for receiving said bar, a flange on said socket memberhaving openings therein, a pin secured to said frame and arranged toengage either of said openings to retain said frame in differentpositions, a nut threaded on said pin for regulating the height of saidframe'relative to said socket member, and a spring bar having a stopthereon for limiting the upward movement of said frame and arranged toengage said nut to hold said nut inadjusted positions on said threadedpin.

4. A sharpener for slicing machine knives, comprising a frame member, aspindle journaled on a fixed axis in said frame member and slidablelongitudinally, a second spindle journaled on a movable axis in saidframe member and slidable longitudinally, grinding discs carried by saidspindles and disposed at opposite sides of the plane of the knife to besharpened, springs for moving said spindles and the grinding discsthereon toward the plane of said knife, abutment members connected tosaid spindles, a cam shaft journaled in said frame member transverselyof said spindles and between said abutment members, separate cams onsaid shaft for engaging said abutment members, a handle for said shaftmovable toward and from the plane of said knife, said cams and abutmentmembers being arranged to cause movement of said grinding discs towardsaid knife when said handle is moved away from the plane of said knife,and a spring for rotating said cam shaft in a direction toautomaticallyretract said grinding discs from said knife when said handle isreleased.

In testimony whereof I have signed my name to this specification on thisseventh day of August A. D. 1923.

WILHELMUS ADRIANUS van BERKEL.

